One of the issues the union rally will focus on is the exploitation of overseas workers on 457 visas being used instead of local workers, but Mr O'Dowd said some industries needed them.

"It depends on the industry itself," Mr O'Dowd said.

"Two meatworks in Rockhampton and one in Biloela, they could not survive without 457s. Actually our prime minister can't survive without a 457 working in her office.

"I believe where Australians can work, they should be given priority."

The LNP members are already ramping up their federal election campaign, five months out.

They are focusing on revealing the negative effects of the carbon tax, potential changes to superannuation and restarting the overseas livestock trade.

"I give you this guarantee, that within two weeks of a change of government, should we be elected - our foreign minister Julie Bishop will be in Indonesia talking about the full restart of the live cattle trade," Senator Macdonald said.